Abstract: The invention pertains to a prepolymer composition comprising a mixture of monomers, oligomers, and polymers obtainable by polymerization of unsaturated monomers consisting of at least one of biscitraconimide, bisitaconimide, and citraconimido-itaconimide, and optionally (co)curable compound selected from bismaleimides, citraconamidomaieimides, and itaconamido maleimides, wherein 5-55 wt. % is monomer, 20-80 wt. % is oligomer having a molecular weight 300 to 3,000, and 10-50 wt. % is polymer having a molecular weight 3,000 to about 80,000, whereas the total content of monomers, oligomers, and polymers in the composition is at least 90 wt. %. The prepolymer can be used for making laminates and prepregs by curing the composition to a polymer.

Abstract: A derivative of aspartic acid is used as a collector for a phosphate containing mineral, such as apatite, in a froth flotation process. According to the invention the collector has a high selectivity for phosphate containing minerals even in the presence of carbonate minerals, such as calcite. The derivative has the formula (I) where RI is a hydrophobic group containing a hydrocarbon group of 6-24 carbon atoms; RII is an alkyl group with 1-7 carbon atoms or a group of the formula (B)yH, in which B is an alkyleneoxy group with 2-4 carbon atoms and y is a number from 1 to 10; and M is a group selected from the group consisting of a cation or hydrogen. Methods for producing the derivative are also described.

Abstract: The invention pertains to a prepolymer composition comprising a mixture of monomers, oligomers, and polymers obtainable by polymerization of unsaturated monomers consisting of at least one of biscitraconimide, bisitaconimide, and citraconimido-itaconimide, and optionally (co)curable compound selected from bismaleimides, citraconamidomaieimides, and itaconamido maleimides, wherein 5-55 wt. % is monomer, 20-80 wt. % is oligomer having a molecular weight 300 to 3,000, and 10-50 wt. % is polymer having a molecular weight 3,000 to about 80,000, whereas the total content of monomers, oligomers, and polymers in the composition is at least 90 wt. %. The prepolymer can be used for making laminates and prepregs by curing the composition to a polymer.

Abstract: A derivative of aspartic acid is used as a collector for a phosphate containing mineral, such as apatite, in a froth flotation process. According to the invention the collector has a high selectivity for phosphate containing minerals even in the presence of carbonate minerals, such as calcite. The derivative has the formula (1) where RI is a hydrophobic group containing a hydrocarbon group of 6-24 carbon atoms; RII is an alkyl group with 1-7 carbon atoms or a group of the formula (B)yH, in which B is an alkyleneoxy group with 24 carbon atoms and y is a number from 1 to 10; and M is a group selected from the group consisting of a cation or hydrogen. Methods for producing the derivative are also described.

Abstract: A process for enhancing the melt strength of polypropylene includes the steps of: mixing the polypropylene with at least 0.1-8 wt. % of an oligomer of maleimide or a derivative thereof, based on the amount of polypropylene, completely or substantially in the absence of peroxide; reacting the polypropylene and oligomer of maleimide or a derivative thereof at a temperature between 150° C. and 300° C.

Abstract: The invention relates to a process for preparing betaines of formula (I) wherein R1 represents a C1-C24 hydrocarbon group, and R2 and R3 independently represent a C1-C3 hydrocarbon group, comprising reacting an aqueous solution of an ethoxylated quaternay ammonium compound of formula (II) wherein R1, R2, and R3 have the same meaning as described above and X− represents a suitable anion, with oxygen or an oxygen-containing gas under alkaline conditions in the presence of a supported and promoted Pt catalyst at a temperature ranging from room temperature to 70° C. Preferably, use is made of a Pt/Bi/C catalyst.

Abstract: Catalyst for dehydrogenating amino alcohols to aminocarboxylic acids or ethylene glycol (derivatives) to oxycarboxylic acids, said catalyst containing zirconium, copper and possibly an additional metal, whereby the cited metals are precipitated as hydroxides, washed, dried, calcined, and reduced, preparable in that zirconium hydroxide is precipitated from an aqueous zirconium salt solution using a base until a pH of 4 to 10 is attained, the aqueous solution of a copper salt and possibly of an additional salt is added to the zirconium hydroxide suspension, and by adding further base copper hydroxide and possibly the hydroxide of the metal contained in the additional salt is precipitated until a pH of 8 to 14 is attained, the suspension obtained is filtered, washed, dried, calcined in air at 450 to 600.degree. C. for 2 to 4 hours and finally reduced at 200 to 250.degree. C. in a hydrogen stream for 2 to 4 hours.

Abstract: A process is provided for preparing polyhydroxycarboxylic acids by the selective oxidation of di-, tri-, oligo- and polysaccharides in an alkaline medium using an oxygenous gas in the presence of palladium on a carrier as catalyst and bismuth as promoter at a palladium concentration in the reaction mixture of at least about 40 mg/l and a molar ratio of bismuth to palladium in the range of from about 1:5 to about 1:40, in which process towards the end of the reaction, as soon as a strong increase is observed in the oxygen concentration in the liquid phase, the oxygen supply is reduced until it is not more than about 20 ppm. In this manner, virtually all of the polysaccharide added beforehand is converted into the desired end product without an unacceptably high concentration of bismuth in the end product.

Abstract: The process for the preparation of benzothiazolyl-2-sulphenamides, by reacting a 2-mercaptobenzothiazole or dibenzothiazolyl 2,2'-disulphide with a primary or secondary aliphatic or cycloaliphatic amine in the presence of hydrogen peroxide as oxidizing agent in an aqueous medium is distinguished in that an aqueous hydrogen peroxide solution is metered at a temperature in the range from 30.degree. to 70.degree. C. into an aqueous suspension of the respective amine and the 2-mercaptobenzothiazole or dibenzothiazolyl 2,2'-disulphide in a ratio in the range between 1.0 and 1.5 mol of amine per mole of 2-mercaptobenzothiazole or per equivalent of dibenzothiazolyl 2,2'-disulphide, preferably in a quantity of below 1.35 mol per mole of 2-mercaptobenzothiazole or per equivalent of dibenzothiazolyl 2,2'-disulphide over a period of at least 60 minutes. The total quantity of water in the reaction mixture should not exceed 1500 g per mole of 2-mercaptobenzothiazole.

Abstract: Ex situ presulfidation of hydrotreating catalysts comprising impregnating the catalysts with an aqueous solution of an organic sulfur compound, e.g. the diammonium salt of 2,5-dimercapto-1,3,4-thiadiazole and 2,2'-dithiodiethanol, followed by drying of the impregnated material. The dried material is activated by contacting it with hydrogen gas at elevated temperature.

Abstract: 2-(aminodithio)thiazoles and 2-(aminotrithio)thiazoles are prepared by reacting a mixture of a 2-mercaptothiazole or a dithiazolyl 2,2'-disulphide with a saturated secondary heterocyclic amine and sulphur in a reaction medium containing an inert organic solvent in the presence of an oxidant. The reaction is carried out in the present of ammonia and a catalyst containing copper, a copper compound or a cerium compound, and the oxidant is molecular oxygen or a gas containing oxygen. In particular, 2-(4-morpholinodithio)benzo-thiazole, which is technically interesting as a vulcanization accelerator, can be prepared in high product yield and virtually without by-products using the oxidant which is less expensive and can be handled with greater ease.

Abstract: A process for the production of thiuram polysulfides substituted by aliphatic, araliphatic and/or cycloaliphatic hydrocarbon radicals is disclosed. In this process, correspondingly substituted secondary amines having a pKa value of .gtoreq.8 are reacted with carbon disulfide and sulfur in a solvent at 0.degree. to 150.degree. C. in the presence of a metal-containing catalyst and oxygen or an oxygen-containing gas.By virtue of its high purity, the thiuram polysulfide obtainable in this way may be directly used for its intended purpose, for example as a vulcanization accelerator or sulfur donor.This process is particularly desirable for the substantially quantitative yields and selectivities and also for its high economy arising from the reaction being carried out in a single stage without expensive auxiliaries and from the elimination of an additional purification step.

Abstract: Disclosed is a process for the ex situ presulfidation of hydrotreating catalysts employing organic sulfur compounds with a boiling point exceeding 100.degree. C. and satisfying the formulaX--R.sup.1 (S--R.sup.2).sub.p S--R.sup.3 --Y (I)wherein p=0, 1 or 2,R.sup.1, R.sup.2, and R.sup.3 may be the same or different and represent alkylene groups having 1-4 carbon atoms,X and Y may be the same or different and have the meaning of --H, --OH, --OR.sup.4 4 or --C(O)OR.sup.5, whereinR.sup.4 has the meaning of an alkyl group or acyl group with 1-3 carbon atoms, andR.sup.5 has the meaning of --H, an ammonium group or an alkyl group with 1-3 carbon atoms.Also disclosed is a process for activating the thus presulfided catalyst.

Abstract: A process for the preparation of aromatic N,N'-disubstituted guanidines is described in which the corresponding aromatic N,N'-disubstituted thioureas are reacted with ammonia and oxygen or with an oxygen-containing gas, in the presence of a solvent and elements acting as catalysts having atomic numbers 21 through 30 in the Periodic Table or the lanthanides or the salts, oxides or complexes thereof.

Abstract: The invention relates to a process for synthesizing alkylene bisdithiocarbamates or the ammonia adducts thereof as well as mixtures that can be synthesized thereby. The starting materials are carbon disulfide, ammonia, a diamine and a metal oxide, which may be manganese(II) oxide, or the hydrate or hydroxide thereof. The metal oxide, its hydrate or hydroxide thereof is allowed to react either with a mixture syntheiszed from an alkylenediamine, carbon disulfide and ammonia in water, or with an aqueous solution of the ammonium alkylene bisdithiocarbamate. The concentration of the individual starting materials both relative to each other and to water is of prime importances as to which compounds in particular are ultimately obtained.

Abstract: A process for synthesizing ammonia complexes of zinc bisdithiocarbamates, starting from carbon disulfide, ammonia, an alkylenediamine and zinc oxide, in which an aqueous mixture of alkylenediamine, carbon disulfide and ammonia in the molar ratio of 1:2:<2, i.e., not 1:2:2, as would be necessary for synthesis of the ammonium alkylene bisdithiocarbamate intermediate product, is reacted with zinc oxide.

Abstract: This invention relates to a process for the production of benzothiazolyl sulphenamides corresponding to the following general formula: ##STR1## in which a corresponding 2-mercaptobenzothiazole or a dibenzothiazolyl-2,2'-disulphide is reacted with a primary or secondary amine at temperatures of from 0 to 100.degree. C. in the presence of ammonia, oxygen, a copper-containing catalyst and a reaction medium containing an excess of the primary or secondary amine or of a mixture of that amine with water and/or a water-miscible organic solvent.Benzothiazolyl sulphenamides are valuable vulcanization accelerators.

Abstract: A process for the preparation of dithiazolyl disulfides by the catalytic oxidation of a 2-mercaptothiazole with ammonia and either oxygen or an oxygen-containing gas at a temperature of between 0.degree. and 150.degree. C.

Abstract: A process for the preparation of thiuram disulfides substituted with aliphatic, cycloaliphatic, araliphatic, or aromatic hydrocarbon radicals, said process comprising reacting a suitably substituted secondary amine with carbon disulfide and in the presence of a tertiary amine or ammonia, oxygen or oxygen-containing gas, a solvent, and a metalliferous catalyst, at a temperature of between 0.degree. C. and 200.degree. C.

Abstract: A process for the preparation of thiuram disulfides substituted with aliphatic cycloaliphatic, araliphatic, or aromatic hydrocarbon radicals, said process comprising reacting a suitably substituted secondary amine having a pK.sub.a .gtoreq.8 with carbon disulfide in a solvent and in the presence of oxygen or oxygen-containing gas, a solvent, and a metalliferous catalyst, at a temperature of between 0.degree. C. and 200.degree. C.